Electrical and Mechanical Runout are two factors that can have a significant affect on Eddy Probe measurements.
While there is little we can do to remove the measurement errors caused by Electrical and Mechanical Runout while the Eddy Probe is in actual use, we can eliminate both of these errors during the testing/calibration process as explained in the following:
Electrical Runout is caused by imperfections and/or variations in the internal composition of the Target Material being monitored. Since the Target Material is typically an alloy made up of a composition of different metals. Each of these different metals can affect the distance measurement capability of the Eddy Probe and thus indicate an erroneous distance between the surface of the Eddy Probe and the surface of the Target Material. By eliminating the possibility of erroneous distance measurement readings during the test/calibration process, we have greater assurance of our test results being correct. Our digital Micrometer adds to this assurance by eliminating the operator judgement errors inherent in using an Analog Micrometer.
By mounting our Target Material on Linear Bearings instead of on a rotating shaft of a Micrometer, we have the exact same Target Material surface area facing the Eddy Probe throughout the entire test/calibration process.
Mechanical Runout is caused by the target material not remaining perfectly parallel with the surface of the Eddy Probe throughout the entire testing/calibration process. When a Target Material is mounted on the shaft of a Micrometer which typically is ¼” diameter, it is difficult to mount the target material so that it is perfectly parallel to the surface of the Eddy Probe. It is even more difficult to maintain that perfect alignment during years of normal use, handling and shipping.
By mounting the Target Material on linear bearings instead of on the shaft of the Micrometer, we make it easy to check and maintain the parallel alignment between the Target Material and the surface of the Eddy Probe. Mounting the Target Material on linear bearings also makes it easier to protect against damage during normal use, handling and shipping between various test sites. Look at the video in the static calibrator section for more information on this.